Resinous product having anion exchange properties and process of producing same



Patented June 24, 1941 RESINOUS PRODUCT HAVING ANION EX- CHANGE PROPERTIES AND PROCESS OF PRODUCING SAME Easton MeloLChicago, 11]., assignor to National Aluminate Corporation, Chicago, 111., a corporation-ot Delaware No Drawing. Application January 20, 1938, Serial No. 185,930

7 Claims.

The present invention relates to a condensation product of improved anion removal capacity and to a process of producing the same. Heretofore exchange materials have been produced from m-phenylenediamine according to the method of Adams 8: Holmes, Chemistry & Industry, 54, 4T (1935), by condensing the free diamine dissolved in an'excess of hydrochloric acid, with a large excess of formaldehyde.

ment thereof will now be described. It is to be understood, however, that this is done solely by way of illustration and is not to be construed as a limitation upon the spirit or scope of my invention.

In carrying out my invention, I prefer to start with m-phenylenediamine, since this material is one of the most readily available members of the class .of aromatic polyamines. However, other The principal object of the present invention 10 members of the class,,-"such as the various benis a new and improved process of condensing zene triamines, the naphthalene polyamines and aryl polyamines with aldehydes, whereby a con the like may be employed if desired, and I do not densation product of increased anion removal wish to limit myself to a particular member of capacity is obtained. the class.

A further object is a method of producing a The aryl polyainines in which the amino condensation product of improved properties groups are meta ;to each other are more satis- Irom aryl polyamines and aldehydes by protectfactory and I prefer to use amines of this type. ing one or some of the several amino groups of The m-phenylenediamine, or other aromatic the polyamine from reaction with the aldehyde. polyamine, is ,iirst converted into the amino- A further object is an improved anion removal 0 acylamino derivative, for example, the monomaterlal produced by such a process. acetyl derivative. This may be accomplished in Other objects will appear as the invention is the usual manner by treating the polyamine with hereinafter more fully described. less than the equivalent amount of acetyl chlo- I have found that the foregoing objects may ride or acetic anhydride. The resulting amino be achieved by condensing an aldehyde in the acetamino derivative; which may be designated presence of a suitable condensing agent with an m-amino/acetanilide, is condensed with formalaryl polyamine derivative which has at least one dehyde in the following manner: 7 /2 parts y free amino group and atleast one amino group weight of m-amino acetanilide hydrochloride is protected from reaction with the aldehyde. After dissolved in 100 parts by weight of water. 28 the condensation has been brought about, the 30 parts by weight of 40% commercial formaldeamino-protecting group is then split off from hyde is added. The reaction mixture is evapothe condensation product. rated to dryness, and a dark red solid is obtained.

The protection of the amino group or groups The residue is crushed and screened and then may-be accomplished in a number of ways well boiled with 25% aqueous sodium hydroxide soluknown in the art. I prefer, however, to convert t n. n l r w h alcoholic Sodium yone or some oi. the amino groups into the acyl droxide solution to insure complete removal of derivatives by interaction with an equivalent the N-acetyl group. amount or acid halide or acid anhydricle. On washing and drying, the hydrolyzed con- The resulting derivative, containing at least ensation product has an anion removal capacity one free amino group and at least one protected which is approximately three times that of the amino group, is then condensed with an aldehyde ,unhydrolyzed intermediate product and over such as aliphaticaldehyde, for example iormtwice that of the m-p'henylenediamine product aldehyde, in the presence of a condensing agent. P par d ccording to the methods of the p ior When the condensation reaction is complete, the art. amino protecting groups are split off by suitable The product obtained by the foregoing process means such ashydrolysis, alcoholysis, ammonolymay be employed to remove acidic compounds sis, or the like, to produce a condensation prodgenerally from solutions thereon. Thus, for exnot having at least one free aryl amino group ample, aqueous solutions of mineral acids such as in the molecule. The product obtained in the sulfuric acid, hydrochloric acid or .phosphoric foregoing manner is characterized by markedly acid; or aqueous solutions of organic acids such improved capacity for anion removal, and is deflas the aliphatic acids, for example, acetic acid; nitely superior in this respect to resins obtained or aqueous solutions of acidic salts such as soaccording to the methods of the prior art. dium acid sulfate, may be rendered substantially In order to disclose the nature of my invention neutral by passing said solutions over or through more clearly, the following preferred embodithe product produced in accordance with my invention. In the case of the acid salts, such as sodium bisulfate, the efliuent water contains no bisulfate ion, the material being converted into the neutral salt. Thus, when an aqueous solution of NaHSO4 containing 50 grains per gallon, was passed through my improved anion-removal material, the total solids content was reduced 41% and the eiiiuent water was neutral, the solids being present as NazSOa.

When the improved condensation product in accordance with my invention is exhausted, it may be regenerated and rendered capable of further anion removal by treatment with an alkaline solution, for example, a dilute ammonium hydroxide solution or a dilute alkali metal hydroxide, such as a 3% solution of sodium hydroxide.

In the foregoing detailed description of my invention it is apparent that many variations in detail may be made without departing from the spirit and scope thereof. Thus many reagents may be employed to protect one or some of the amino groups of the aryl polyamine, such as the monoacyl derivatives obtained from reaction with the acid chloride or acid anhydride of propionic acid, butyric acid, isobutyric acid, pentanoic acid, and the higher members of the series. Furthermore, monoaryl polyamines other than those hereinbefore. particularly mentioned may be used as starting materials. Thus naphthalene polyamines may be employed if desired. It is also apparent that other aldehydes such as acetaldehyde and the like may be used in place of formaldehyde. Likewise, other condensing agents for bringing about the condensation between the aldehyde and the protected polyamine maybe used. In general any compound .which is either acid or basic may be used forthis purpose. Thus, alkalis such as sodium hydroxide are known to bring about the reaction. Likewise, mineral acids such as sulfuric acid, hydrobromic acid, phosphoric acid and the like; acid salts, such as sodium acid sulfate, etc.; and organic acids such as acetic acid, etc., are eflective. Other equivalents will be readily apparent to anyone skilled in the art.

Many other variations in detail will be apparent to those skilled in the art. I therefore intend to be limited only in accordance with the following patent claims.

Iclaim:

1. The process of producing a resinous condensation product having anion exchange properties, which comprises condensing a. mono-N- acylated aryl polymine with a suficient amount of an aldehyde selected from the group consisting of formaldehyde and acetaldehyde, to form an aryl-amine-aldehyde resinous condensation product, and thereafter de-acylating the N-acylamino group of the said resinous condensation product, whereby to convert said group to an amino group.

2. The process of producing a resinous condensation product having anion exchange properties, which comprises condensing mono-N- acylated aryl diamine with a sumcient amount of formaldehyde to form an aryl amine-formaldehyde resinous condensation product, and thereafter deacylating the N-acylamino group of the said resinous product by,hydrolysis, whereby to convert said group into an amino group.

3. The process of producing a resinous condensation product having anion exchange properties, which comprises condensing monmN- acylated phenylenediamine with a sufilcient amount of formaldehyde to produce an andamine aldehyde resinous condensation product, and thereafter de-acylating the said resinous product whereby to produce a resinous product having at least one free amino group, and characterized by anion exchange properties.

4. The process of producing a resinous condensation product having anion exchange properties, which comprises condensing monc-N- acylated m-phenylenediamine in the presence of a hydrohalide, with a sumcient amount of formaldehyde to form an aryl amine-aldehyde resinous condensation product, and thereafter treating said resinous product with an alkaline-reacting aqueous solution to convert the N-acylated amino group therein to a free amino group.

5. The process of producing a resinous condensation product having anion exchange properties, which comprises condensing mono-N- acyiated m-phenylenediamine hydrohalide with a sufiicient amount of formaldehyde to form an aryl amine-aldehyde resinous condensation product, and treating the said resinous product with an aqueous alkaline-reacting solution to produce a product having at least one free amino group.

6. A resinous condensation product of unknown structure and characterized by anion exchange properties, comprising the reaction product obtained by the process of claim 1.

7. A resinous condensation product of unknown structure and characterized by anion exchange properties, comprising the reaction product obtained by the process of claim 5.

EASTON MELOF. 

